Building out from the foundation of a beautiful outlook for near-term organic growth, Endeavour Silver (NYSE: EXK) continues to expand an exciting portfolio of development properties to construct a sound fortress of sustained growth potential.

Like a skilled blacksmith, Endeavour will now have multiple irons in the fire from which to arrange its priority targets for future mine constructions, and this latest joint venture option looks like a sweet one. Endeavour will team up with fertilizer and lithium producer Sociedad Quimica y Minera de Chile (NYSE: SQM) to earn a 75% stake in that company's El Inca silver-gold development properties in northern Chile. Covering 447 hectares (1,104 acres), the properties are thought to reside within the southern extension of the same Bolivian silver-tin belt that hosts Coeur d'Alene Mines' (NYSE: CDE) San Bartolome mine and Silver Standard Resources' (Nasdaq: SSRI) Pirquitas mine.

The primary "El Inca" asset is known to host silver-lead-zinc sulphide mineralization, including four major vein structures of up to four meters in width "that outcrop for up to 1.6km along strike." Codelco, Chile's state-owned copper miner, encountered average silver grades of 227 grams per ton before mining at El Inca ceased in 1982, and by then Codelco had identified a resource of 7.6 million ounces of silver. Clearly, Endeavour is excited by a perceived exploration potential that would dwarf the asset's modest historical resource.

For that matter, the option agreement also covers two additional properties nearby that were likewise mined historically by Codelco until 1978, and which recorded a combined historical resource of 5.6 million ounces silver at an extremely attractive grade of 523 grams per ton. Together with Endeavour's 2011 options of the La Presidenta and Lomas Bayas properties, Endeavour has amassed a substantial set of attractive development properties in northern Chile. If only one of those prospects yields a deposit as rich in silver as San Bartolome or Pirquitas, Endeavour will have optioned its way into a phenomenal long-term growth trajectory.

Meanwhile, Endeavour is still delivering powerful organic growth, a 31% increase in silver-equivalent production for the second quarter. The company pulled in $7.5 million in profit, and once again took the strategic decision to hold back a portion of mine production from the market until prices improve somewhat. Just as it has done very successfully in recent quarters, Endeavour ended the quarter with a mineral inventory of more than 1.2 million silver-equivalent ounces, which is ready for sale as precious-metal prices inevitably improve.

As production from the El Cubo mine (recently acquired from AuRico Gold (NYSE: AUQ) with plenty of room for operational improvements under Endeavour's proven management team) enters the picture from the third quarter forward, I expect Endeavour's near-term-growth story alone to boost this stock during the second half while the market awaits its preliminary glimpses of exploration results from these newly optioned properties in Chile (and several in Mexico as well). I'll be heading back down to Mexico before too long for a timely inspection of the improvements that Endeavour will bring to El Cubo, and I encourage readers to watch for my report by bookmarking my article list or following me on Twitter.

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